A Predicted Correlation Between Age Gradient and Star Formation History in FIRE Dwarf Galaxies

Understand

We explore the radial variation of star formation histories in dwarf galaxies simulated with Feedback In Realistic Environments (FIRE) physics.

• The sample contains 9 low-mass field dwarfs with M_ star = 10^5 - 10^7 M_sun from previous FIRE results, and a new suite of 17 higher mass field dwarfs with M_star = 10^7 - 10^9 M_sun introduced here.
• We find that age gradients are common in our dwarfs, with older stars dominant at large radii.
• The strength of the gradient correlates with overall galaxy age such that earlier star formation produces a more pronounced gradient.